![background image](http://html.mh-extra.com/html/icom/ic-7400/ic-7400_service-manual_612265024.webp)
*This output level of a standard signal generator (SSG) is indicated as SSG’s open circuit.
RX PEAK
RECEIVER
TOTAL GAIN
NOISE
BLANKER
5 - 8
5-4 RECEIVER ADJUSTMENTS
ADJUSTMENT
ADJUSTMENT
ADJUSTMENT CONDITION
MEASUREMENT
VALUE
POINT
UNIT
LOCATION
UNIT
ADJUST
1
2
3
1
1
2
• Displayed freq. : 14.100000 MHz
• Mode
: USB
• Set following selections, controls
and functions as:
[RF/SQL]
: Center
[PITCH]
: Center
[AGC] : OFF , [ATT] : OFF
[NB] : OFF , [RIT] : OFF
PBT1 : Center, PBT2 : Center
[P.AMP]
: P.AMP1
IF Filter
: 2.4 kHz
[NR] switch
: OFF
[NOTCH] switch: OFF
• Preset L215 (RF unit) to 2 rotation
downside from top of the coil’s case.
• Connect an SSG to [ANT1] con-
nector and set as:
Frequency
: 14.101500 MHz
Level
: 10 µV* (–87 dBm)
Modulation
: 1 kHz/±3.5 kHz dev.
• Receiving
• Mode
: FM
• Filter
: 15 kHz
• Set an SSG as :
Frequency
: 14.100000 MHz
Level
: 1 mV* (–47 dBm)
Modulation
: 1 kHz/±5.0 kHz Dev.
• Receiving
• Displayed freq. : 0.03000 MHz
• Set an SSG as :
Level
: OFF
• Receiving
• Displayed freq. : 14.100000 MHz
• Mode
: USB
• Filter
: 2.4 kHz
• [P.AMP]
: OFF
• Set an SSG as :
Frequency
: 14.101500 MHz
Level
: 160 mV* (–3 dBm)
Modulation
: 1 kHz/±5.0 kHz dev.
• Receiving
• Displayed freq. : 14.100000 MHz
• Mode
: USB
• [P.AMP]
: P.AMP1
• [NB]
: OFF
• [NB LEVEL]
: 50%
• Set an SSG as :
Frequency
: 14.101500 MHz
Level
: 18 µV* (–82 dBm)
Modulation
: OFF
and apply following signal to [ANT1]
connector.
• Preset R200 (MAIN unit) to the 12
o’clock position.
• Receiving
• [NB]
: ON
• Receiving
Rear
panel
MAIN
MAIN
Connect an AC milli-
volt meter to [EXT
SP] connector with
an 8
Ω
load.
Connect an distortion
meter to [EXT SP]
connector with an
8
Ω
load.
Connect an AC milli-
volt meter to [EXT
SP] connector with
an 8
Ω
load.
Connect an oscillo-
scope to the check
point CP1460.
Connect an oscillo-
scope to the check
point CP200.
Maximum audio output
level
Minimum distortion
level
Minimum noise output
level
4.0 Vp-p
Maximum noise level
At the point where the
voltage just reduces.
RF
MAIN
MAIN
L252,
L251
,
L242,
L241
,
R218
R1469
L201,
L202,
L203
,
R200
100 msec.
1 msec.
Summary of Contents for IC-7400
Page 1: ...HF VHF TRANSCEIVER i7400 SERVICE MANUAL ...
Page 63: ...to S LOGIC board J303 DS1002 9 2 DISPLAY BOARD TOP VIEW 9 3 for free by RadioAmateur eu ...
Page 72: ...9 12 1 9 18 10 BOTTOM VIEW RF UNIT for free by RadioAmateur eu ...
Page 74: ... BOTTOM VIEW CTRL UNIT 9 14 for free by RadioAmateur eu ...
Page 76: ... BOTTOM VIEW TUNER UNIT 9 16 for free by RadioAmateur eu ...
Page 78: ...9 18 BOTTOM VIEW PA UNIT for free by RadioAmateur eu ...
Page 92: ...1 1 32 Kamiminami Hirano ku Osaka 547 0003 Japan S 13811HZ C2 2002 Icom Inc ...